Every 5ish years or so. My CPU have the same speed as the CPUs released in 2005, albeit more energy efficient so it generate less heat, and still run the games just fine. Upgraded my graphic card last year though.
Although the oldest part of my computer is my keyboard, which I've used over 15 years now. I have no plans on replacing that one though, it's very comfy, but I will upgrade the second oldest part soon I think, which is the OS. I'm still using Windows XP.
^^ More or less this. I less upgrade, and more just fully overhaul my entire computer, all that will remain this time around is likely my case. I don't really see the point in upgrading every 2 years or so, as long as you buy more or less new stuff every 5 years, it'll last and play anything that comes out in that time period just fine. Maybe it'll be lower end of spectrum by the end of the, but it will still play them. I'm currently running dual 9600 GTX NVIDIA cards, 3Gigs of 800MHZ Ram, Quad-Core 2.6GHZ Processor, 750GIG HDD, Windows XP SP3. It's been more or less 5 years, not sure if I"ll be able to upgrade this year, but next year for sure. I'll probably go to an i7 Processor, likely Quad-core 3.0GHZ, Dual 460GTX NVIDIA cards, Windows 7, a new MOBO that will support the i7 Processor, and 8GIGs of 1600 ram(might go for the next tier above t hat though). Not to worried about buying the 500 series of NVIDIA cards, not when I'm running dual 460's. As long as it supports DX11, I'll be happy. That will run me just fine for the next 5 years
